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ELECTRICAL COMPONENTS
345
SV64031
Engine compartment
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ELECTRICAL COMPONENTS
347
No.FUSEAMPERECIRCUIT
26 MPX±B10
Power window system,
Air conditioning,
Gauges and meters,
Theft deterrent system
27 P RR P/W20Power window system
28 SRS±B7.5SRS system, Door lock system
29 TV7.5Television
30 OBD7.5On±board diagnosis system
31 IGN7.5
SRS system,
Multiport fuel injection
system/sequential multiport fuel
injection system,
Cruise control system
32 ECU±B120
Theft deterrent system,
Door lock system,
Interior light, Trunk light,
Vanity light, Ignition switch light,
Map light, Door courtesy lights,
Power window system,
Air conditioning,
Gauges and meters
33 ALT±S7.5Charging system
34 ETCS15Electronic throttle control
system
35 AM220
Starting system, SRS system,
Multiport fuel injection
system/sequential multiport fuel
injection system, Cruise control
system
36 HORN10Horn
No.FUSEAMPERECIRCUIT
37 RADIONO.120Audio
38 TURN±HAZ15Turn signal lights
39 EFI25
Multiport fuel injection
system/sequential multiport fuel
injection system,
Emission control system,
Engine immobiliser system
40 DRL NO.230Daytime running light system
41 DRL NO.17.5Daytime running light system
42 H±LP L LW R15Left±hand headlight
(low beam), Fog lights
43 H±LP R LW R15Right±hand headlight
(low beam)
44 ABS27.5Anti±lock brake system
45 SPARESpare fuse
46 SPARESpare fuse
47 SPARESpare fuse
48 H±LP LUPR10Left±hand headlight
(high beam)
49 H±LP R UPR10
Right±hand headlight
(high beam),
Service reminder indicators and
buzzers
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ELECTRICAL COMPONENTS
349
Checking battery exterior
SV64002
1Terminals 2Hold±down clamp
Check the battery for corroded or loose connections,
cracks, or loose hold±down clamps.
1. If the battery is corroded, wash it off with a solution of warm
water and baking soda. Coat the terminals with grease to
prevent further corrosion.
2. If the connections are loose, tighten the clamp bolts ± but
do not overtighten.
3. Tighten the hold±down clamp only enough to keep the
battery firmly in place. Overtightening may damage the battery
case.
NOTICE
Make sure the engine and all accessories are turned off before performing maintenance.
When checking the battery, remove the ground cable
first and reinstall it last.
Be careful not to cause a short circuit with tools.
Take care no solution gets into the battery when washing it.
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ELECTRICAL COMPONENTS
350
Checking battery condition
Checking by indicator
SV64016
Check the battery condition by the indicator color.
1BLUE ± Good condition.
2WHITE ± Charging necessary. Have the battery checked
by your Lexus dealer.
3RED ± Have the battery checked by your Lexus dealer.
NOTICE
Do not refill the battery with water.
BATTERY RECHARGINGPRECAUTIONS
During recharging, the battery is producing hydrogen
gas.
Therefore, before recharging:
1. If recharging with the battery installed on the vehicle, be
sure to disconnect the ground cable.
2. Make sure the power switch on the recharger is off when
connecting the charger cables to the battery and when
disconnecting them.
CAUTION
Always charge the battery in an unconfined area. Do
not charge the battery in a garage or closed room
where there is not sufficient ventilation.
Only do a slow charge (5 A or less). Charging at a
quicker rate is dangerous. The battery may explode
causing personal injuries.
NOTICE
Never recharge the battery while the engine is running.
Also, be sure all accessories are turned off.
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ELECTRICAL COMPONENTS
351
CHECKING AND REPLACING THEBLADE TYPE FUSES
SS64009
Driver's side kick panel
SS64012a
Passenger's side kick panel
SV64017
Engine compartment 1Spare fuses 2Pull±out tool
1. Turn the ignition switch off and open the fuse box lid.
Determine which fuse may be causing the problem. The lid of
the fuse box shows the name of the circuit for each fuse.
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ELECTRICAL COMPONENTS
354
CAUTION
Always use a genuine Lexus fuse or equivalent for
replacement. Never install an ordinary wire ± even for
a temporary fix. This may cause extensive damage and
possibly a fire.
NOTICE
Before replacing the fuses, have the cause of electricaloverload determined and repaired by your Lexus dealer.
ADDING WASHER FLUID
SS64013
If the washer tank becomes nearly empty, add washer
fluid.
You may use plain water as washer fluid. However, in cold
areas where temperatures range below the freezing point, use
washer fluid containing antifreeze. This product is available at
your Lexus dealer and most auto parts stores. Follow the
manufacturer's directions for how much to mix with water.
NOTICE
Do not use engine antifreeze or any other substitute because it may damage your vehicle's paint.
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3
GAS STATION INFORMATION
Fuel selection:
Select premium unleaded gasoline with an Octane Rat-
ing of 91 (Research Octane Number 96) or higher for
optimum engine performance. However, if such pre-
mium type cannot be obtained, you may temporarily use
unleaded gasoline with an Octane Rating as low as 87
(Research Octane Number 91).
Fuel tank capacity:
66 L (17.5 gal., 14.5 lmp.gal.)
Engine oil:
ºToyota Genuine Motor Oilº or equivalent
Oil grade: API grade SL ºEnergy±Conservingº or ILSAC
multigrade engine oil.
Recommend oil viscosity ± SAE 5W±30 if normal
temperatures are below 38 C (100F)
Oil capacity: L (qt., lmp.qt.)
Drain and refill with filter 5.4 (5.7, 4.8)
without filter 5.1 (5.4, 4.5)
See page 315 for detailed information.
Engine coolant:
Capacity: 7.5 L (7.9 qt., 6.6 lmp.qt.)
Coolant type ± ºToyota Genuine Long Life Coolantº or
equivalent
With ethylene±glycol type coolant for a proper corrosion
protection of aluminum components For checking the engine coolant, see page 319.
Do not use alcohol type antifreeze or plain water alone.
Automatic transmission:
Fluid type ± Toyota Genuine ATF Type T±IV
See page 324 for detailed information.
Tire information:
See page 331 through 341 for detailed information.
Tire pressure:
Tire size: 225/45ZR17, 215/45ZR17 or P205/55R16 89V
Tire pressure: cold tires
kPa (kgf/cm
2 or bar, psi)
Ti
re sizeFrontRear
225/45ZR17 ± 240 (2.4, 35)
215/45ZR17 230 (2.3, 33) 230 (2.3, 33)
P205/55R16 89V 230 (2.3, 33) 230 (2.3, 33)
For sustained high speeds above 160 km/h (100 mph), in
countries where such speeds are permitted by law, add the
tire pressure given below to the front tires and rear tires, but
never exceed the maximum cold tire pressure molded on the
tire sidewall.
225/45ZR17 70kPa (0.8 kgf/cm
2, 0.7 bar, 10 psi)
215/45ZR17 70kPa (0.8 kgf/cm2, 0.7 bar, 10 psi)
P205/55R16 89V
Sedan 70kPa (0.8 kgf/cm
2, 0.7 bar, 10 psi)
SportCross Front: 70kPa (0.8 kgf/cm2, 0.7 bar, 10 psi)
Rear: 90kPa (0.9 kgf/cm2, 0.9 bar, 15 psi)
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2.
Maintenance procedures for the engine, chassis,
body, electrical system, and more, are clearly
explained and illustrated.
Periodic maintenance and tune±up
Periodic maintenance and tune±up helps to prevent small
problems from growing into larger ones later on. The repair
manual outlines exactly what maintenance is required and
clearly explains how to do the work yourself step±by±step.
Areas covered include such things as spark plug replacement,
valve clearance adjustment and engine oil and filter
replacement.
Where to obtain theRepair Manual
The repair manual for IS300 written in English, may be
purchased as applicable from any Lexus dealer.
Pub. Name: 2003 IS300 Repair Manual
Pub. No.: Vol.1 RM980U1 Vol.2 RM980U2
2003 IS300 from Aug. '02 Prod. (OM53439U)